IBM DCAS-32160 - Ultrastar 2.1 GB Hard Drive, Технические характеристики

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11.18 Diagnostics
The file will execute a self test at power on or when a Send Diagnostics command is issued with the self test
bit set.
The diagnostics are to assure the correct operation of the file and to verify that the check circuits detect fault
conditions.
11.18.1 Power on Diagnostics
At power on time the following tests are executed:
1. Test the microprocessor's internal RAM.
2. Test the HDC.
3. D o a read/write test on sector buffer RAM.
4. Check if the 12 volt line is active.
5. Initialize and check the servo system is functioning correctly.
6. Check the spindle's R P M .
7. Seek to a correct cylinder.
11.18.2 Diagnostics Command
The tests executed as a result of the Send Diagnostics command with the self test bit set to a one differs from
the tests executed at power on.
The spindle motor must be at the correct speed for the Diagnostics
command to be executed. If the motor is not at the correct speed, a N O T R E A D Y status will be returned
in the sense byte.
The Diagnostics command will execute the following tests:
1. Test the adapter section of the file as follows:
a. Assure the ECC circuits work correctly.
b. D o a read/write test on sector buffer RAM.
2. Check the spindle's R P M .
3. Seek to a correct cylinder.
4. Write the certain area in reserved area.
5. Read from the area.
11.18.3 Diagnostics Fault Reporting
Faults detected before successful completion of the adapter section could prevent the file from responding to
a selection.
Faults detected after the successful completion of the adapter section will be reported as Check Condition
status to the initiator on the first command issued after a fault is detected except for the Inquiry command.
The Inquiry command will always respond with good status.
Detecting a fault during power on will not
terminate execution of the diagnostics nor will it terminate the power on process.
Faults detected during a Send Diagnostics command will report a Check Condition as end status.
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O E M Spec. of DCAS-34330/32160